Process and apparatus for forming metal plates for dentures



Jan. 12, 1932. G. L. VAN ALLEN PROCESS AND APPARATUS FOR FORMING METAL PLATES FOR DENTURES Filed March 23, 1928 2 Sheets-Sheet ATTORNEYS.

Jan. 12, 1932.

PROCESS AND G. L. VAN ALLEN 1,840,991

APPARATUS FOR FGRMING METAL PLATES FOR DE NTURES Filed March 23, 1928 2 Sheets-Sheet 2 IplVENTOR 1/ G M/M ATTORNEY5 Patented Jan. 12, 1932 UNITED s rArE-s PATENT OFFICE GEORGE L. VAN ALLEN, OF NEWARK, NEW JERSEY A SSIGNOR T BAKER & CO. INC.,

CORPORATION OF NEW JERSEY IROCESS AND APPARATUS FOR IQRMING METAL PLATES FOR DENTURES I Applloation filed March 23, 1928. Serial No. 264,096.

The objects of this invention are to se cure an im roved, rocess of drawin or shaing ,out of; sheet metal the forms which are employed as the bases for building up dentures,

' -either partial or full; to secure more perfect and accurate forms or .plates, and to avoid any cracks or splits in'the same such a s'destroy their smooth ,surfaceor continuity and have to be laboriously corrected by hand; ;to expedite and facilitate the formation of such plates, and'cheapen as well as improve theproduction of them, and to obtain other :advantages and results as may be brought out by the followingdescription.

15. Referring to the accompanying drawings,

inwhich like characters of reference indicate the same parts throughout the several views,

. Fig. .1 is a plan view of a die such as is zoyemploye'd according to my invention;

.f Fig. 2is' aplan viewof a blank of thin sheet metal which is to be formed upon said die;

, Fig. 8 is an-edge View of said blank;

Fig. 4 is a cross-section of the die with the blank-thereon after receiving an impression;

Fig. 5 is. aplan view of the same;

Fig. 6 is a plan view of the blankas shown ii -Figs. 4 and 5 trimmed for the next impression;

' Fig. 7 shows in cross-section similar to Fig. 4 the blank after another impression;

'Fig. 8 is a plan view of the blank after still further trimming;

Fig. 9 shows in cross-section the blank with its middle portion drawn to its final form; and

Fig. 10 shows it after its final trimming and ready for use.

In said drawings, a die 1 is shown having a central portion constituting what is known in the art as a model, the particular one illustrated being for a full upper denture and having a depressed middle portion 2 corresponding to the roof of the mouth and a surrounding portion 3 corresponding to the gums. It will be understood that a thin sheet-metal blank is desired to be pressed into the exact form of the said model, includ- 60 ing the outer Wall of the part 3, to form a baseiupon which a set of artificial teeth can be formed.

By my. invention, I carry the material of which the die 1 is formed, from the base of the outer wall 4 of the gum portion 3 outwardly away therefrom a distance and then upward, preferably fiaringly as at 5, to substantially the plane of the top of the gum portion 3, and then outward in said plane, as at 6, sufiiciently far to give a firm support and hold to the outer marginal portions of the sheet-metal blank when it is laid upon the die. The die as shown comprises an outer ring 7 in which the shaped metal 8 is enclosed, but this is immaterial to the invention; the die essentially comprises the central model surrounded by the groove 9 and raised portion 10 with its supporting top surface 6.

WVith a die such as described, the thin sheet metal blank 11, as shown in Figs. 2 and '3, is laid upon the top of the die, being substantially of the same shape andsize therewith, and then pressure is applied in any common and well-known manner, such as by means of a piece of rubber with a follower back of the same, the die, rubber, and follower being all enclosed in a suitable ring or cylinder of a press. This is common and well-known in the art and isbelieved to require no further description here. As is also old'in the art, the drawing or forming is done in steps, and the disk or plate annealedbetween the successive steps and Figs. 4 and 5 show the completion of the, first step. It will be noted that marginal portions '12 of the sheet metal'blank are supported upon the top 6 of the outer raised portion 10 of the die, as the forming takes place and progresses, so that the metal is ,against the outer walls 5 of the said groove 9 as wellasupon the top 6 of the outer por tion of the die, the metal of the plate being swaged downwardly into thegroove 9, asat j13, and also :in'to the center hollow portionQ of the die, as at "14. I

The outer raised portion of the die does not, shape any portions of the. sheet-metal T blank for use in theidenture, but simply supports or holds them in order to secure a 'peri ectformation ofthe sheetfmetalagainst the outer walls of the gum portion .3 of the die.

Therefore, as the'outer portion of the blankis extended further down into the groove-Qand 'particularly in contactwith vits outer wall, asfat l b, Fig. 4, the peripheral, marginal I portion of the disk can in practice be trimmed away and .clispen ed -wi Fo examp i Fig. 6, 17 indicates the blank 16 as it is shown in Figs; 4 and 5,. afteriit has .been trimmed peripherally, so that it does not overlap quite so far upon the top'supporting surface 6 of the die; 18' in Figi? "indicates the blank after has received anotherimpression, and 19 in Fig. 8 shows it'still furthertrimmed so that it has practically no horizontalportion at all to overlie upon the s top 6 of'the'outer raised portion. of the die.

'20 in Fig. 9 indicates the blank after still another pressure in the die which practically i conforms it thereto, and after "this the outer marginal portion2l is'trimmed off entirely to the line "of the baseof the gum, and the plate assumes itsfinal form indicated by 22 1" Havingthus described the in .Iclaim is: n v I i l. A process of formingmetal plates for in Fig.10.

It will tion of the blank still bears against the outer wall 5 of thegroove f thedie and is sufficiently supported thereby; the trimming must'be done in accordance with thesup- 'portneeded .by" said peripheral portion of the blank,and atjno time extend inward too 'far to remove such support. Otherwise it can be varied in detailby the operator, and of course the number of impressions that the blank receives in thedie is immaterial.

While I have shown the blank 11 as a disk or circular, obviously it isnot restricted to that shape Furthermore, while Ihave illus-' trated the invention in the production of a plate for a full upper denture, it is just as applicable to the production of plates for full partial dentures'either 7 lower dentures or .for upper or lower. 7 I

Various modifications can be made 1n Icarrying out the invention, by those skilled in the art, without departing from the spirit and scope thereof; and therefore I do'not be understood that the trimming can be done'because-theouter peripheral poreral top portion and central sunken model .portiona H p 7 3. 'A die for forming'metal plates'fo'r den- "tures; comprising an outer peripheral top p r ie lcent altsun eninede JPQ PiP and an annular groove between said peripheral top portion .andcentral model portion, the

said grooveflaringupwardly outward."

outer wall of 4. A process of 'forming metal plates for dentures, consisting in supportinga blank at its peripheral marginal portion outside amodel, indenting its central portion 'onto'z the model and into an annular groove -between saidfmodel' and peripheral marginal portion, and trimming away-all of the blank ,outside said model; 4

5. A process of forming metal plates for dentures,'consisting in supporting a blank at its peripheral marginal portion outside a model, indenting its central portion onto the model and into anwannular groove between said modeland peripheral marginal portion by'successive 1mpress1ons,-and peripherally trimming the blank with said impressions.

progressively 6. A process of forming'metal platesfor dentures, consisting in supporting a blank at its peripheral "marginal portion outside a model, .indenting its central portion onto the model and into an annular groove between'said model and peripheral marginal;

portion-"by successive impressions,f and peripherally trimming the blank progressively as it conforms to the said groove.

I GEORGE L. VAN ALLEN.

desire tobe understood as limiting myself 7 except as requiredby the following claims y when construed in'the light of the prior art.

dentures, consisting in supporting a 'blank at its peripheral marginal portion and indenting its central portion ontoa model and into an annulargroove between said model 1 and peripheral marginal portion by succes-, sive -impressions', 'and trimming away the vention, what 7 

